phLXR

("PHP LeXical analyzeR" or "PHP Language Cross Referencer") is a tool for
cross-referencing PHP aplication source trees. It's written in PHP using a
modified version of class.layout by http://www.vhconsultants.com/, relies
heavily on PHP's PCRE (preg_*) functions, and uses MySQL.

The idea appeared when I tried to make use of LXR (http://lxr.linux.no/) on
an NT machine - the absence of a win32 port of Glimpse rendered the task
impossible. And while I quickly abandoned the target of building
a cross-referencing tool for C sources (I don't think I'm good enough for
this. :), I realized the PHP hackerdom would certainly welcome this - I know
I would. :)

As soon as SF put on PHP 4.0.5 (phLXR uses preg_replace_callback() pretty much) I'll
set up a live demo on the source of phLXR.
Meanwhile, you can see how it (currently) looks on these two static pages:
output of browse
& output of source.
As these two examples show, this is still in very early stages.
WARNING: don't look at the page with anything else than IE 5+! (If you
wanna help with HTML, let us know. :)